xref: /linux/arch/sh/kernel/cpu/sh2a/clock-sh7264.c (revision 96ac6d435100450f0565708d9b885ea2a7400e0a)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * arch/sh/kernel/cpu/sh2a/clock-sh7264.c
4  *
5  * SH7264 clock framework support
6  *
7  * Copyright (C) 2012  Phil Edworthy
8  */
9 #include <linux/init.h>
10 #include <linux/kernel.h>
11 #include <linux/io.h>
12 #include <linux/clkdev.h>
13 #include <asm/clock.h>
14 
15 /* SH7264 registers */
16 #define FRQCR		0xfffe0010
17 #define STBCR3		0xfffe0408
18 #define STBCR4		0xfffe040c
19 #define STBCR5		0xfffe0410
20 #define STBCR6		0xfffe0414
21 #define STBCR7		0xfffe0418
22 #define STBCR8		0xfffe041c
23 
24 static const unsigned int pll1rate[] = {8, 12};
25 
26 static unsigned int pll1_div;
27 
28 /* Fixed 32 KHz root clock for RTC */
29 static struct clk r_clk = {
30 	.rate           = 32768,
31 };
32 
33 /*
34  * Default rate for the root input clock, reset this with clk_set_rate()
35  * from the platform code.
36  */
37 static struct clk extal_clk = {
38 	.rate		= 18000000,
39 };
40 
41 static unsigned long pll_recalc(struct clk *clk)
42 {
43 	unsigned long rate = clk->parent->rate / pll1_div;
44 	return rate * pll1rate[(__raw_readw(FRQCR) >> 8) & 1];
45 }
46 
47 static struct sh_clk_ops pll_clk_ops = {
48 	.recalc		= pll_recalc,
49 };
50 
51 static struct clk pll_clk = {
52 	.ops		= &pll_clk_ops,
53 	.parent		= &extal_clk,
54 	.flags		= CLK_ENABLE_ON_INIT,
55 };
56 
57 struct clk *main_clks[] = {
58 	&r_clk,
59 	&extal_clk,
60 	&pll_clk,
61 };
62 
63 static int div2[] = { 1, 2, 3, 4, 6, 8, 12 };
64 
65 static struct clk_div_mult_table div4_div_mult_table = {
66 	.divisors = div2,
67 	.nr_divisors = ARRAY_SIZE(div2),
68 };
69 
70 static struct clk_div4_table div4_table = {
71 	.div_mult_table = &div4_div_mult_table,
72 };
73 
74 enum { DIV4_I, DIV4_P,
75        DIV4_NR };
76 
77 #define DIV4(_reg, _bit, _mask, _flags) \
78   SH_CLK_DIV4(&pll_clk, _reg, _bit, _mask, _flags)
79 
80 /* The mask field specifies the div2 entries that are valid */
81 struct clk div4_clks[DIV4_NR] = {
82 	[DIV4_I] = DIV4(FRQCR, 4, 0x7,  CLK_ENABLE_REG_16BIT
83 					| CLK_ENABLE_ON_INIT),
84 	[DIV4_P] = DIV4(FRQCR, 0, 0x78, CLK_ENABLE_REG_16BIT),
85 };
86 
87 enum {	MSTP77, MSTP74, MSTP72,
88 	MSTP60,
89 	MSTP35, MSTP34, MSTP33, MSTP32, MSTP30,
90 	MSTP_NR };
91 
92 static struct clk mstp_clks[MSTP_NR] = {
93 	[MSTP77] = SH_CLK_MSTP8(&div4_clks[DIV4_P], STBCR7, 7, 0), /* SCIF */
94 	[MSTP74] = SH_CLK_MSTP8(&div4_clks[DIV4_P], STBCR7, 4, 0), /* VDC */
95 	[MSTP72] = SH_CLK_MSTP8(&div4_clks[DIV4_P], STBCR7, 2, 0), /* CMT */
96 	[MSTP60] = SH_CLK_MSTP8(&div4_clks[DIV4_P], STBCR6, 0, 0), /* USB */
97 	[MSTP35] = SH_CLK_MSTP8(&div4_clks[DIV4_P], STBCR3, 6, 0), /* MTU2 */
98 	[MSTP34] = SH_CLK_MSTP8(&div4_clks[DIV4_P], STBCR3, 4, 0), /* SDHI0 */
99 	[MSTP33] = SH_CLK_MSTP8(&div4_clks[DIV4_P], STBCR3, 3, 0), /* SDHI1 */
100 	[MSTP32] = SH_CLK_MSTP8(&div4_clks[DIV4_P], STBCR3, 2, 0), /* ADC */
101 	[MSTP30] = SH_CLK_MSTP8(&r_clk, STBCR3, 0, 0),	/* RTC */
102 };
103 
104 static struct clk_lookup lookups[] = {
105 	/* main clocks */
106 	CLKDEV_CON_ID("rclk", &r_clk),
107 	CLKDEV_CON_ID("extal", &extal_clk),
108 	CLKDEV_CON_ID("pll_clk", &pll_clk),
109 
110 	/* DIV4 clocks */
111 	CLKDEV_CON_ID("cpu_clk", &div4_clks[DIV4_I]),
112 	CLKDEV_CON_ID("peripheral_clk", &div4_clks[DIV4_P]),
113 
114 	/* MSTP clocks */
115 	CLKDEV_ICK_ID("fck", "sh-sci.0", &mstp_clks[MSTP77]),
116 	CLKDEV_ICK_ID("fck", "sh-sci.1", &mstp_clks[MSTP77]),
117 	CLKDEV_ICK_ID("fck", "sh-sci.2", &mstp_clks[MSTP77]),
118 	CLKDEV_ICK_ID("fck", "sh-sci.3", &mstp_clks[MSTP77]),
119 	CLKDEV_ICK_ID("fck", "sh-sci.4", &mstp_clks[MSTP77]),
120 	CLKDEV_ICK_ID("fck", "sh-sci.5", &mstp_clks[MSTP77]),
121 	CLKDEV_ICK_ID("fck", "sh-sci.6", &mstp_clks[MSTP77]),
122 	CLKDEV_ICK_ID("fck", "sh-sci.7", &mstp_clks[MSTP77]),
123 	CLKDEV_CON_ID("vdc3", &mstp_clks[MSTP74]),
124 	CLKDEV_ICK_ID("fck", "sh-cmt-16.0", &mstp_clks[MSTP72]),
125 	CLKDEV_CON_ID("usb0", &mstp_clks[MSTP60]),
126 	CLKDEV_ICK_ID("fck", "sh-mtu2", &mstp_clks[MSTP35]),
127 	CLKDEV_CON_ID("sdhi0", &mstp_clks[MSTP34]),
128 	CLKDEV_CON_ID("sdhi1", &mstp_clks[MSTP33]),
129 	CLKDEV_CON_ID("adc0", &mstp_clks[MSTP32]),
130 	CLKDEV_CON_ID("rtc0", &mstp_clks[MSTP30]),
131 };
132 
133 int __init arch_clk_init(void)
134 {
135 	int k, ret = 0;
136 
137 	if (test_mode_pin(MODE_PIN0)) {
138 		if (test_mode_pin(MODE_PIN1))
139 			pll1_div = 3;
140 		else
141 			pll1_div = 4;
142 	} else
143 		pll1_div = 1;
144 
145 	for (k = 0; !ret && (k < ARRAY_SIZE(main_clks)); k++)
146 		ret = clk_register(main_clks[k]);
147 
148 	clkdev_add_table(lookups, ARRAY_SIZE(lookups));
149 
150 	if (!ret)
151 		ret = sh_clk_div4_register(div4_clks, DIV4_NR, &div4_table);
152 
153 	if (!ret)
154 		ret = sh_clk_mstp_register(mstp_clks, MSTP_NR);
155 
156 	return ret;
157 }
158